Luoshuang's GPULightmass

Thank you, I will try that!

Hey Jimbohalo10 can i get a link to download GPUL 5.4?

hi @STrike3Ds,

There is the 5.4 BINARY sort of preview which is packed 27GB WinRar, built on ue5main 17th July 2023

There may be a binary for official version 5.4 about 3 months probably when 5.4.1 official binary comes out

Announcement of Luoshuang’s GPULightmass (LGPU) 5.4 as downloadable BINARY.

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Sorry but… I think you are quite wrong.

Appart of the limitation of the GI contribution of rect lights, GPULL works absolutely fine.

Just reading your first 2 points and both are wrong, as GPULL works perfect with point lights, it’s also available for the latest Unreal version too… where do you take the info from?

In addition, GPULL is much more faster than GPULE and it works way better, as GPULE is quite broken, as many users are frequently reporting in its dedicated forum’s thread.

I could continue, but I think this is more than enough. Is Epic paying you, maybe?

Hi @Miguel1900
No its a strange promotion of his website, which is has many format errors and CAN ONLY PURCHASE US Dollars.

Amazingly there is a quote of FOUR hours for an RTX 3060 for a paid project. I expect that to be approximately 40 minutes on LGPU using same hardware.

Most ArcViz users users LGPUL. EPIC GPUL is supposed to support the new functions like HDRI Nanite Tessellation.

EGPU now works Landscape as long as you LOAD MY PATCH :rofl:

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Dear @Jimbohalo10

Sorry for my low intelligence.

I’m using unreal 5.3.1, could you direct me to a correct link and how to install GPULigthmass, please?

I have a GTX 1050Ti and I’m struggling to do my projects in Lumen, I want this method now.

Thank you very much for the help.

hi @cretzsf ,
The Luoshuang’s GPULightmass - 5.3.1/2 announce post links to GitHub and the README tells you how to install

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HI @ATNeo I had the same issue with Rectangle lights, very strange and sharp shadows, also no matter what setting changed in actor details, no effect. As the last option, I changed Lighting quality from Preview to High, in Editor, under Build tab. That fixed the problem. As I understand, Rect lights are not supported by GPU Lightmass, so it uses parallel CPU computation, so changing light and lightmass settings in the Editor will affect the scene.

Hi @Jimbohalo10 ,

Do you know if the Skylight is something like clamped to a max value Intensity of 10, 100, or 1000 (not sure)? I’m switching to use extended luminance EV100 exposure, so highest values are used in all light sources, but Sky Light doesn’t seem to not increase anything more after that Intensity value.

Thank you in advance!

hi @Miguel1900
in BaseEditor.ini:569:

[/Script/UnrealEd.AssetViewerSettings]
+Profiles(ProfileName="Default",DirectionalLightIntensity=2.620000,DirectionalLightColor=(R=0.990000,G=0.839850,B=0.732600,A=1.000000),SkyLightIntensity=0.880000

So its reasonable to say its been set to
SkyLightIntensity=0.880000 initially
in BaseLightmass.ini

bUseFilteredCubemapForSkylight=true

[DevOptions.ImportanceTracing]
AdaptiveSkyVarianceThreshold=.5
bUseRadiositySolverForSkylightMultibounce=True

[DevOptions.IrradianceCache]
; Sky occlusion has less noise than normal GI, dont blur away details
SkyOcclusionSmoothnessReduction=.5

[DevOptions.StaticLightingMediumQuality]
AdaptiveSkyVarianceThresholdScale=1

[DevOptions.StaticLightingHighQuality]
AdaptiveSkyVarianceThresholdScale=.5


[DevOptions.StaticLightingProductionQuality]
AdaptiveSkyVarianceThresholdScale=.5

So you can see there is a lot to play with, but LGPU probably is a combination of the values. When looking at the code this seems to be set to use only Production Quality.
a float of 0.50 is hardcoded throughout the CUDA code.

There is no way to adjust the as its fixed value into LGPU

CPU Lightmass says

Note that the physical lighting units are measured in cd/m2, like the Sky Light or Emissive Materials. Sun and Sky sources have that range in the thousands of units, which it does hand-in-hand with physical cameras where the Exposure Value (EV) are in the range of EV100:14 (see the "Sunny 16" rule). However, with the HDRI Backdrop asset, it is not required to use physically correct values, but you may need to set the EV to something significantly lower than the EV100:14. It's also worth noting that some HDR images range from 0 to 5.0 or greater than 5 cd/m2 while others are ranging from 0 to 100K units. This means that when you swap HDR images, there may be a noticeable difference in brightness changing.

Epic GPU Lightmass (EGPU) :rofl: :rofl: 5.3 documentation says

Stationary Sky Light is Not Supported Support is planned in a future release of the engine.

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Thank you very much for your info @Jimbohalo10 ! There are some things to play with, so I will keep researching about this! (Even if I think It won’t be changed, but maybe, at least, will try to boost the ‘internal’ HDR brightness).

Thanks!

tks very much

Hello all,

A question has been asked about Rectangular Lights (Rect Lights). They are they are processed by CPU Lightmass not processed by LGPU Lightmass.

The normal default for LGPU is Lighting Production set in BaseLightmass.ini at the bottom section.

Now people are leaving the Lighting setting as Preview. This means that Rect Lights look distorted and low-quality. Some users see it as a fault in LGPU.

You will need to set Lighting Production which will use more CPU and take more overall time to bake.

The way to solve this is the make Rect Light into Emissive light as has been described previously in past posts.

I hope this clears up the mystery with Rect Lights’ quality

Hi.
At the beginning of baking, the GPU works, then switches to the processor and counts something on it for 40 minutes… And only after that, everything is counted on the GPU very quickly… There is sun and sky in the scene, there are no other sources, and in the project there are only walls and that’s it. We bypassed this moment of switching to the CPU somehow, but I don’t remember how. Something LGPU does not support in my opinion, and therefore it takes a long time to count on the processor …
Who can help me with this?

The picture shows just the moment when it is being counted on the processor
photo_2024-03-06_13-24-55

hi @nikldreamer1 ,

Check your Lightmass Importance Volume | Unreal Engine 5.0 Documentation
are correct

Well the original documentation may help

(FireflyClampingThreshold has been loosened to allow more contrast from skylight and correct brightness for emissives

 - if you start to see fireflies from sky or emissive you may want to set it to lower values like 10.0 (in BaseLightmass.ini))


This installation overwrites your BaseLightmass.ini so you want to back it up if you have modified its parameters.

If you want to keep your BaseLightmass.ini,

 set bUsePhotonMapping and bUseRadiositySolverForSkylightMultibounce to false to avoid CPU computation.

Originally there was no support for static Skylight in UE4, however this seems to have been implemented at sometime.
The usual problem is Rect Lights are not implemented and therefore CPU based.

There are no intentions to implement these functions because they must be compatible with Unreal 4.

To really know what is going on you need to look at the Swarm Log to see what has happened, may be copy the text to notepad and upload the *.txt file

This is a particularly difficult question, which the remaining LGPU participants may not easily answer

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Thank you very much…))) They helped a lot

Hi Jimbohalo, can you send me the link to Luoshuang’s GPULightmass (LGPU) 5.4, i can’t download from mircrosoft’s page

hi @b_bach_h ,
The problem is that for some reason the upload has been deleted

I have updated the original post at
Luoshuang’s GPULightmass 5.4 (ue5main 21st July 2023) early preview BINARY Announcemant

Follow Progress/ Announcements on LGPU 5.4 and LGPU 5.5 at
Luoshuang’s GPULightmass 5.5 beta preview, called (LGPU55) and 5.4.x eventually

Thank you for the info @Jimbohalo10 ! Let see if version .0 final is releaded before than a month.

Just for asking, when you update it to a new version, like 5.4.0, how difficult is to update if after to 5.4.1, for example? (As many times it even still works without needing to update too, right?)